1. Field of the Invention
The present invention generally relates to a method for forming a through-hole in an insulating substrate by using a laser beam.
2. Description of the Related Art
Conventionally, there is a method of forming a through-hole in an insulating substrate by radiating a laser beam from a laser source to the insulating substrate (see Patent Document 1).    Patent Document 1 U.S. Pat. No. 5,493,096
Typically, in a case of forming multiple through-holes in an insulating substrate by using a laser beam, the following steps are repeated.
1) Move a process target (i.e. insulating substrate) to a predetermined position relative to a laser beam, and stop the insulating substrate at predetermined position;
2) Form a first through-hole in a first radiation area of the insulating substrate by radiating the laser beam;
3) Stop the radiation of the laser beam;
4) Move the insulating substrate to another position relative to the laser beam; and
5) Form a second through-hole in a second radiation area of the insulating substrate by radiating the laser beam.
However, with the method using the above-described steps, the insulating substrate is required to be moved from one position to another position relative to the laser beam whenever another through-hole is to be formed (processed). Therefore, this method requires a large amount of time to form multiple through-holes and degrades the efficiency of processing multiple through-holes.